The present invention relates, in general, to electrical power service apparatus and, more particularly, to full enclosure covers for watthour meters.
Electrical power is supplied to an individual site or service by external electrical power line conductors located above or below ground. In a conventional arrangement, electrical power line conductors are connected to terminals in a watthour meter socket mounted on a wall. Electrical load conductors are connected to another set of terminals in the meter socket and extend to the electrical distribution network in the building. The watthour meter has conductors connectible to both pairs of terminals in the meter socket to measure the electrical power drawn through the load conductors.
Older style bottom connected meters have the aforementioned terminals located below the meter which is fixedly mounted on a back plate of an enclosure. The line and load conductors are also attached to the terminals.
A cover is pivotally attached to the back plate to sealingly encompass the watthour meter mounted on the back plate. Lock connections may be provided between the cover and the back plate to receive a padlock or a wire seal which is useful in providing an indication of tampering with the meter enclosure.
A transparent glass window is mounted in the cover in a position to expose the watthour meter power readout dials to viewing from outside of the enclosure. The glass is held in place by spring clips removably mounted in plates attached by welding, to the inside surface of the cover. A seal material may also be employed between the glass and the surrounding inside cover surface to seal the window aperture from the exterior environment.
However, the glass is susceptible to breakage, either due to vandalism or from normal exposure to the environment. The spring clips are also susceptible to breakage, rusting, etc. thereby allowing the glass to separate from the cover surface.
These conditions allow the ingress of rain and debris into the interior of the enclosure, any of which can lead to serious and dangerous situations if such rain or debris comes in contact with the power carrying conductors and terminals within the enclosure.
The spring clips are also susceptible to separation from the mounting plates. Since the spring clips are formed of metal, the spring clips can result in a short circuit if the spring clip falls across conducting portions of the terminals or conductors, again leading to a dangerous and possibly explosive event.
Thus, it would be desirable to provide a replacement window for an overall watthour meter enclosure which addresses the deficiencies encountered with previously devised glass windows in such enclosures. It would also be desirable to provide a replacement window for an overall watthour meter enclosure which can be easily installed in overall existing enclosure covers. It would also be desirable to provide a replacement window for an overall watthour meter enclosure in which the entire front cover can be replaced by a single piece member which addresses all of the deficiencies encountered with previously devised metal covers with glass windows as well as providing long term reliable use, complete sealing of the watthour meter and terminals within the enclosure, and easy viewability of the meter power indicator dials. It would also be desirable to provide a replacement window/cover for an overall watthour meter enclosure which has a higher degree of vandalism resistance and, at the same time, provides an easy indication of any attempt to unauthorizedly tamper with the enclosure.